Culture of pineapple plants



Patented Sept. 30, 1947 CULTURE, OFAPINEAPPLE. PLAN TS. V

Ferdinandl. Mehrlich, Honolulu,

Territory of Hawaii, assignor' to Hawaiian Pineapple Coinpany, Limited; Honolulu, Territory of Hawaii,

a corporation of Hawaii N Drawing. Application April 30, 1943,,v

Serial. N 0. 485,181

- 14 Claims.

This invention relates apple plants and to'methods for chemically controlling the growth thereof. More particularly, the invention concerns the application topineapple plants of those synthetic organic com to the culture of pine:

pounds known as plant hormones which, une,

der certain conditions of application, have a gen.- eral growth stimulating effect on plants. As examples of such synthetic plant hormones may be mentioned naphthalene-and indole compounds such as alpha naphthaleneacetic, beta naph-v thoxy acetic, indoleaceticandiindolebutyric acids, and amides and'alkali metal salts thereof. j

An object of the invention is to provide'novel methods of pineapple cu1ture inwhich, by'th'e utilization of such compounds, the size and weight of the pineapple fruit are substantially in: creased and its quality is improved. Another 'object is to provide such amethod by which, the time of differentiation and flowering and/or the date of maturation of the fruit may be changed asdesired. As is .well known, difierentiation is the change of the plant from. vegetative to flower: ing condition.

In conventionallpineapple culture, considerable difliculty may be experienced. bylthe weakening of the peduncle (fruit stem) allowing the fruit to fall over, exposing largeareas of'the' fruit tow the direct rays of the sun. This resultsin considerable damage to the fruit and loss in recovery-from sun-scald or sunburn of the fruit. A further object of the invention-is to provide a novel method forkpineapple. culture in which, through the use of synthetic hormones, the stem is strengthened, the fruit is kept erect, sun-scald is reduced, and the size and Weight of the fruit are increased.

Another object of the invention is to efiec't a mechanical strengthening of the outer tissues of thefruitwhich are commonly referred to "as the shell. of the fruit. It is desirable to strengthen these tissues as a means of limiting bruising of the fruit in theharvesting operations and in the transportation and other handling of the fruit.

, I have made the important discovery .that'the beneficial results which it is the object of this invention to produce, can be obtained by application of synthetic hormones directly to the grow ing plant at proper times and. in proper concentrations and quantities as will be hereinafter fully explained. 7 By means of this discovery, I am enabled to bringabout an increase in the weight pffthe pineapple fruit '.by as, much asj'a, pound or. more per fruit. while and correspondingly, in creasingits size anojimpro ing its quality. This amounts toan increase of eight tons or mor fru it peracre. Lalso accomplish a delay in the ma turation of the pineapple crop of as much as two months; an, advance ordelay, as desired,;in.the time ofdiirerentiation and'fiowering by a matter of weeks; and as'trengthening of the peduncle;

In establishing, the -.ioregoing, numerous tests havebeen conducted on many plants andin dif+ ferentlfields, thefefiects, being checked by com parison withiuntreated plants in the same 105 cality. I

In, an illustrative set of these tests,*which will serve to illustrate the process as applied to the improvement of the fruit'and'peduncle, the plants treated had in all cases differentiated and were in variousstages cidevelopment between diflerentiation and, maturity of the fruit. The-plant hormones employed, were alpha naphthalene-e acetic. acid, potassium naphthalene acetate: and alpha naphthylacetamide. The hormone was mixed in a liquid carrier 'consisting of water oroi water and lanolin emulsionwhich' Wassprayedor poured over thehearts and leaves of the plants in. approximately the quantityof 25" cc; to cc'; of mix-to; each plant. The concentrations offmix usediwere, in proportions of; parts ofhormone to parts of carrier 1250.0; 1:1;000;1:5,000;l:10,000 1:20;000, 1':33,500. W

In all cases except ,wherethe fruit'was siib= stantially, fully grown. at the time. of treatment,

' the followingefiects were produced,

1. MaturatiOhflHd. ripening 01v the. fruit were delayed, from one week-to two months, generally from two to'threeweelgs. I 1

2., The weight andsize .of theifruitwere in creased, the fruit of, thetreated plants beingire quently Imore than .a', ,pound .heavier thanj 1. the. fruit of the comparativeuntreated' plants; f 1 w (3.,The, quality,of thejfruitwas improved.

4. The fruit, of. the, treated plants had larger, more robust eyes than the fruit'of the 'compara ,tiveuntreated. plants. I

5.Th'e peduncles of the treatedjpl' lllts were larger, stronger andmore fibrous 'thanthose. of theicomparativeuntreated plants; In the cases .Wherefl'thefruit was, full growniat the time of treatment no. significant ,efiectsjwere observed. J o. 'Th'eefieets were jgreatestjand approximately the, same with the hormone concentrations, of

irom 1,000 togsasouparisearrier to one part', of hormone i applied, j at any sta e ,.of.,.plant dev lop; ment bet een difterentiation'and half grow;

'the,fruit..,

I ,Te'stsnag isn wn,that;the; icuv n ssiorgit to 33,500 parts carrier to with substantially the same effects,

tion in concentrations of 3 dry dusting powder mix for purposes of the present invention is about one-tenth that of the liquid mix at the same concenrations so that, if such a mix is employed, it should have about ten times the proportions of hormone to carrier of the liquid mixture. Th-us,'in placeof the liquid mix of a range of hormone concentrations of from 1,000 one part of hormone, I may employ, a dry dusting powder mix in proportions of about 100 to 3600 parts dusting powder to one part of hormone.

Successive applications at spaced intervals sufficiently long to insure complete absorption by the plant of the hormone from the previous application, such as the intervals of last flower, onequarter grown fruit, one-half grown fruit, etc., produced the same degree as compared with the single application of correponding hormone concentration. Successive applications at spaced intervals of only a. few days produced the same effects but to an enhanced degree. Applications should be particularly directed onto the' forming fruit.

I have also found that by applying synthetic hormones to the pineapple plants in advance of the normal date of differentiation, their'differentiation and flowering may .be retarded or advanced as desired'according to the concentration of hormone employed, and the maturation date of the ensuing crop will be correspondingly retarded or advanced, provided hormone treatments are not applied during orafter'differentiation.

Thus, by applying synthetic hormones to the pineapple plants only in advance of difierentiaone part hormone to from 1,000 to 10,000 parts of liquid carrier I have substantially delayed differentiation and flowering of the plants and also, correspondingly, maturation of the ensuing crop; whereas, if the hormones are applied to the plants in lesser. concentrations of one part hormone to from 16,500 to 200,000 parts of carrier, the opposite effects of precocious differentiation, floweringand corresponding advance of the date of crop maturation are produced. For the same effects, the concentrations of dry mixes should be about ten times that indicated for the liquid-mixes. The mix is sprayed, poured or dusted onto the hearts and leaves of the plants. Suitable quantities are 25 cc. to 100 cc. liquid mix per plant. V

Acceleration or retardation may be'produced in this manner, varying from a few days to a matter' of weeks, depending on how far in advance of the normal difierentiationdate thejtreatment is given. Within the concentration ranges mentioned, the higher concentrations produce more extensive changes than the weaker concentra tions, though repeated applications of a weaker concentration mix may be employed to produce the same result as a single application in greater concentration. a

This treatment has no substantial effect on the size and weight of the fruit or on its peduncle structure, merely changingrits maturation date. For purposes of delaying crop maturation, therefore, the post-difierentiation treatment previously described is more advantageous. However, by advancing the crop maturation date of some only of the plants by such pre-differentiation treatment, the grower may attain a definite prolongation of his harvesting periods and reduction of peak loads, particularly ration of some only of hisplants either by postefiects but to an enhanced gasses differentiation or pre-diiferentiation treatment as previously described. Also, pre-differentiation treatment which accelerates differentiation may be employed to offset in whole or in part a delay in crop maturation resulting from post-differentiation treatment of the same plants; and, conversely, if the plants are given a pre-difierentia- 7 tion treatment which retards their differentiation if he also delays .matutherefor, the hormone concentration and are then given the post-differentiation treatment, the delay of their crop maturation date beyond the normal date is greater than that which would result from either treatment alone.

The hormone treatments may be applied to pineapple plants after the first crop; that is, in the ratoon crop stage, as well as before the first crop, with like benefits. The fruit bearing suckers ofplants in the ratoon stage generally develop unequally, some being much further matured than others at any given time. Such plants may be treated with hormone, in concentrations previously mentioned as suitable for postdiiferentiation treatment to increase crop size, at a time when some of the suckers have passed the differentiation stage and others have not. This treatment will produce different effects on individual suckers according to their stage of development, delaying maturation and improving the crop of the suckers which have passed differentiation and, as these concentrations are within the range of concentrations suitable for producing precocious differentiation, accelerating differentiation of the other suckers.

In the practice of the invention, I prefer to apply the hormone in a liquid carrierwhich may suitably be water or a water and lanolin or a water and oil emulsion or a solvent such as a1- cohol or the like. If a dry powder is used as a carrier, talc, clay, bentonite, kaolin and the like are suitable. The mixture is sprayed, poured or dusted on the plants, care being taken to insure direction of a substantial quantity into the hearts of the plants. Beta naphthoxy acetic acid, alpha naphthaleneacetic acid and alpha naphthylacetamide are considered preferred hormones for purposes of the invention because they are efiicient and comparatively inexpensive and easily obtainable, but other hormones may, of course, be used with like effect as previously noted. A single hormone may be used, or several may be used in combination.

Having now described and explained preferred practices of the invention, what I desire to claim and secure by Letters Patent is:

1. A method for the culture of pineapple plants which comprises applying to the plants, after differentiation and prior to half growth of the fruit, a plant hormone in sufficient quantity to cause a delay in the maturation of the fruit and an increase in the size thereof.

2. A method for the culture of pineapple plants which comprises applying to the fruit, after formation, a plant hormone in sufficient quantity to cause an increase in the size thereof.

3. A method for the culture of pineapple plants which comprises applying. to the plants, after differentiation and prior to full maturity of the fruit, a plant hormone in sufficient quantity to cause an increase in the size and strength of the peduncles of the plants.

4. A method for delaying and improving the fruit yield of pineapple plants which comprises treating the plants after differentiation and prior to full maturity of the fruit; with a mixture of a plant hormone and a liquid carrier medium of said mixture being of the order of one part hormone to from 1,000 to 33,500 parts of liquid medium.

5. A method for delaying and improving the fruit yield of pineapple plants which comprises treating the plants after differentiation and prior to full maturity of the fruit with a mixture of a plant hormoneand a powdered carrier medium therefor, the hormone concentration of said mixture being of the order of one part hormone to from 100 to 3,600 parts of powdered medium.

6. A method for reducing sun-scald and bruising in pineapple culture which comprises strengthening the peduncles of the pineapple plants and strengtheningthe shell tissues of the fruit by applying to the plants, after differentiation and prior to half growth of the fruit, a mixture of a plant hormone and a liquid carrier medium therefor, the hormoneconcentration of said mixture being of the order of one part hormone to from 1,000 to 33,500 parts of liquid medium.

7. A method for reducing sun-scald and bruising in pineapple culture which comprises strengthening the peduncles of the pineapple plants by applying to the plants, after diiferentlation and prior to full maturity of the fruit, a mixture of a plant hormone and a powdered carrier medium therefor, the hormone concentration of said mixture being of the order of one part hormone to from 100 to 3,600 parts of powdered medium.

8. A method for changing the date of crop maturation of pineapple plants which comprises applying to the hearts and leaves of the plants prior to crop maturation beta naphthoxy acetic acid contained in a liquid carrier medium in the proportion of at least one part of beta naphthoxy acetic acid to 200,000 parts of carrier medium.

9. A method for changing the date of crop maturation of pineapple plants which comprises applying to the hearts and leaves of the plants prior to crop maturation beta naphthoxy acetic acid contained in a powdered carrier medium in the proportion of at least one part of beta naphthoxy acetic acid to 20,000 parts of carrier medium.

10. A method for the culture of pineapple plants which comprises applying to the fruit. after formation, a plant hormone in-sufiiclent quantity to cause an increase in the size thereof, said hormone being selected from the group consisting of alpha naphthaleneacetic, beta naphthoxy acetic, indoleacetic and indolebutyric acids, and amides and alkali metal salts thereof.

11. A method for the culture of pineapple plants which comprises applying to the plants, after differentiation and prior to full maturity of the fruit, a plant hormone in sufiicient quantity to increase in the size and strength of the peduncles of the plants, said hormone being Proc. Am. Soc.

selected from the group consisting of alpha naphthaleneacetic, beta naphthoxy acetic, indoleacetic and indolebutyric acids, and amides and alkali metal salts thereof.

12. A method for delaying and improving the fruit yield of pineapple plants which comprises treating the plants after difl'erentiation and prior to full maturity of the fruit with a mixture of a plant hormone and a liquid carrier medium therefor, the hormone concentration of said mixture being one part hormone to from 1,000 to 33,500 parts of liquid medium, said hormone being selected from the group consisting of alpha naphthaleneacetic, beta naphthoxy acetic, indoleacetic and indolebutyric acids, and amides and alkali metal salts thereof.

13. A method for delaying and improving the fruit yield of pineapple plants which comprises treating the plants after differentiation and prior to full maturity of the fruit with a mixture of a plant hormone and a powdered carrier medium therefor, the hormone concentration of said mixture being one part hormone to from to 3,600 parts of powdered medium, said hormone being selected from the group consisting of alpha naphthaleneacetic, beta naphthoxy acetic, indoleaceticand indolebutyric acids, and amides and alkali metal salts thereof.

14. A method for the culture of pineapple plants which comprises applying to the fruit, after formation, a plant hormone in sufficient quantity to cause a delay in the maturation of the fruit.

FERDINAND P. MEHRLICH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Traub', Inducing Flowering In the Pineapple, Hort. Sci, vol. 37, pp. 521-525 (1940).

Pearse, Effect of Phenylacetic Acid," J. Pomology Hort. Sci., Vol. 14, pp. 865-375 (1937). Zimmerman, Formative Eifects Induced With Beta-Napthoxyacetic Acid, Contrib. Boyce Thompson Inst., vol. 12, pp. 1-14 (1941).

Crocker, "Similarities in the Effect of Ethylene and the Plants Auxins, Contrib. Boyce Thompson Inst., vol. 7, No. 3, pp. 231-248 (1935).

Killelfer, Plant Hormones, published May 10, 1940, in Ind. Eng. Chem. News Edition, vol. 18, No. 9, pp. 395-399.

July 8, 1941 

